parlov-elicit 0.3.0

Elicitation engine: strategy selection and probe plan generation for parlov.
Documentation
//! `DependencyDeleteElicitation` -- probes with DELETE to detect resource dependency differentials.
//!
//! Sends a plain DELETE with no body on both baseline and probe requests. The oracle
//! signal is the server returning 409 (the existing resource has dependents that block
//! deletion) versus 404 (the resource does not exist).

use http::Method;
use parlov_core::{NormativeStrength, OracleClass, Technique, Vector};

use crate::strategy::Strategy;
use crate::types::{ProbeSpec, RiskLevel, StrategyMetadata};
use crate::util::build_pair;
use crate::ScanContext;

fn metadata() -> StrategyMetadata {
    StrategyMetadata {
        strategy_id: "dependency-delete-elicit",
        strategy_name: "Dependency Delete Elicitation",
        risk: RiskLevel::OperationDestructive,
    }
}

fn technique() -> Technique {
    Technique {
        id: "dependency-delete",
        name: "Dependency-blocked DELETE probe",
        oracle_class: OracleClass::Existence,
        vector: Vector::StatusCodeDiff,
        strength: NormativeStrength::May,
    }
}

/// Elicits existence differentials via a DELETE that may be blocked by resource dependencies.
pub struct DependencyDeleteElicitation;

impl Strategy for DependencyDeleteElicitation {
    fn id(&self) -> &'static str {
        "dependency-delete-elicit"
    }

    fn name(&self) -> &'static str {
        "Dependency Delete Elicitation"
    }

    fn risk(&self) -> RiskLevel {
        RiskLevel::OperationDestructive
    }

    fn methods(&self) -> &[Method] {
        &[Method::DELETE]
    }

    fn is_applicable(&self, _ctx: &ScanContext) -> bool {
        true
    }

    fn generate(&self, ctx: &ScanContext) -> Vec<ProbeSpec> {
        let pair = build_pair(
            ctx, Method::DELETE,
            ctx.headers.clone(), ctx.headers.clone(),
            None, metadata(), technique(),
        );
        vec![ProbeSpec::Pair(pair)]
    }
}

#[cfg(test)]
mod tests {
    use super::*;
    use http::HeaderMap;

    fn make_ctx() -> ScanContext {
        ScanContext {
            target: "https://api.example.com/users/{id}".to_string(),
            baseline_id: "1001".to_string(),
            probe_id: "9999".to_string(),
            headers: HeaderMap::new(),
            max_risk: RiskLevel::OperationDestructive,
            known_duplicate: None,
            state_field: None,
            alt_credential: None,
            body_template: None,
        }
    }

    #[test]
    fn risk_is_operation_destructive() {
        assert_eq!(DependencyDeleteElicitation.risk(), RiskLevel::OperationDestructive);
    }

    #[test]
    fn generate_returns_one_item() {
        assert_eq!(DependencyDeleteElicitation.generate(&make_ctx()).len(), 1);
    }

    #[test]
    fn item_is_pair_variant() {
        let specs = DependencyDeleteElicitation.generate(&make_ctx());
        assert!(matches!(specs[0], ProbeSpec::Pair(_)));
    }

    #[test]
    fn probe_body_is_none() {
        let specs = DependencyDeleteElicitation.generate(&make_ctx());
        let ProbeSpec::Pair(pair) = &specs[0] else { panic!("expected Pair") };
        assert!(pair.probe.body.is_none());
    }

    #[test]
    fn technique_strength_is_may() {
        let specs = DependencyDeleteElicitation.generate(&make_ctx());
        assert_eq!(specs[0].technique().strength, NormativeStrength::May);
    }
}